imx: add macro to detect whether USB has been initialized

This macro allows to detect whether the boot ROM initialized USB
already (serial downloader). This is helpful to reliably detect
if the system has been recovered via USB serial downloader.

Signed-off-by: Stefan Agner <stefan.agner@toradex.com>
Acked-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>

diff --git a/arch/arm/include/asm/arch-mx6/imx-regs.h b/arch/arm/include/asm/arch-mx6/imx-regs.h
index 4314392..4f01b20 100644 (file)
--- a/arch/arm/include/asm/arch-mx6/imx-regs.h
+++ b/arch/arm/include/asm/arch-mx6/imx-regs.h
@@ -996,5 +996,12 @@ struct pwm_regs {
        u32     pr;
        u32     cnr;
 };
+
+/*
+ * If ROM fail back to USB recover mode, USBPH0_PWD will be clear to use USB
+ * If boot from the other mode, USB0_PWD will keep reset value
+ */
+#define        is_boot_from_usb(void) (!(readl(USB_PHY0_BASE_ADDR) & (1<<20)))
+
 #endif /* __ASSEMBLER__*/
 #endif /* __ASM_ARCH_MX6_IMX_REGS_H__ */